Question

i know how to solve it but i’m just not used to the bigger numbers. could someone still walk me through step by step?

Answer 1

$\cfrac{42}{70}~~ = ~~\cfrac{u}{55}\implies \cfrac{(14)3}{(14)5}~~ = ~~\cfrac{u}{55}\implies \cfrac{3}{5}=\cfrac{u}{55}\implies \cfrac{3(55)}{5}=u \\\\\\ 3\cdot \cfrac{55}{5}=u \implies 3\cdot 11=u\implies 33=u$